The capture and analysis of pollutants and solid trash that originate from curbside gutters.
Solid trash that accumulates in a gutter and is not swept away ultimately enters a drain somewhere. Similarly, liquid flowing in the gutter enters these drains. Both of these are troublesome. Solid material must be cleared out of drains and check dams so the systems do not become plugged and the surrounding areas become flooded in a heavy storm.
The liquids often include pernicious material such as insecticides, fertilizers and engine oil. These will ultimately reach a river, a lake or an ocean, and will pollute them as a source of water or food. Such problems have long been tolerated, because the extent of their usage has only gradually challenged the capacity of the earth to contend with them. However, it is now becoming evident that the earth""s capacity to deal with these has been over-estimated.
The costs of keeping drainage systems open have been assumed to be an acceptable and necessary charge. The increasing awareness of these expenses and problems is leading to vigorous efforts to reduce them at their very source by detecting and detaining them at or very near to their source.
Thus, it is a matter of importance to become aware of what the trash is and where it comes from. Similarly, the source of liquid or dissolved pollutants must be learned before they can be stopped.
It is an object of this invention to provide an economical and conveniently serviced device to capture the trash and pollutants so they can be identified and their sources learned.
There is a problem inherent in such traps. The retained trash could itself clog the drain if it already filled the trap when a heavy rainfall occurs. Accordingly it is another object of this invention to provide a trap which can open and dump the clogging material when it is heavily burdened and the water flow is rapid. While this will release some trash into the drainage system, the downstream system will have previously been kept clear, and the amount of trash disgorged into it will be too small to plug the larger system. Meanwhile, before this event occurs, solid trash can be collected, analyzed and carried away, and the pollutants defined.
It is an object of this invention to provide a conveniently serviced system for this purpose, which has a provision to be over-ridden when adverse conditions occur, such as a heavy storm.
According to this invention, a frame is fitted into a curb opening through which runoff water and accompanying trash is normally expected to pass into a catch basin. The base includes a horizontal track inside the catch basin and a sill.
According to this invention a cage-like trap is mounted to the track so it can slide through the opening and into and out of the catch basin. It has an open front face facing outwardly with the opening, and bounding sides at least some of which are pervious to water flow.
The trap includes a rear face facing into the catch basin. This rear face is hinged so as to open and permit unrestricted flow of water in the event of high flow rates such as a heavy rain. In such event, the contents, if any, of the trap will be washed into the catch basin.
Because of the track relationship, the trap can be removed by an axial pull, and its contents analyzed and carried away.
As an optional feature of the invention a filter may be placed beneath the trap where it will collect pollutants of interest as defined by the selected filter medium. If desired, the filter trays holding the filter pads can be supported directly from the base, with the advantage that when the trap is removed for servicing, the filter pads will be directly accessible through the opening.
As a preferred but optional feature, the rear face of the trap can be biased toward its closed position by a hinge spring, or held by magnets, in any event to be opened when a heavy water flow arrives.
The above and other features of this invention will be fully understood from the following detailed description and the accompanying drawings, in which: